Device for protecting coatings on wires



Oct. 8, 1957 J. P. TESMER 2,808,805

DEVICE FOR PROTECTING commas ON WIRES Filed Jan. 6, 1955 2 Sheets-Sheet l ,l/VVE/VTOH. JOHN R TESMER,

his Affbr ney.

Oct. 8, 1957 J. P. TESMER 2,303,305

DEVICE FOR PROTECTING COATINGS ON WIRES Filed Jan. 6, 1955 2 Sheets-Sheet 2 0711mm Will/4 /N VE N TOR.

JOHN R TE SMER,

his Attorney.

United States T DEVICE FOR PROTECTING COATINGS N WIRES John P. Tesmer, Cleveland, Ohio Application January 6, 1955, Serial No. 480,082

Claims. (Cl. 118-65) This invention relates to an improved device for protecting the surface of freshly coated wires emerging from a molten metal coating bath.

Although my invention has general application for baths of molten metals whose surfaces tend to oxidize, it is particularly useful for aluminum baths. The usual procedure for applying aluminum coating to ferrous wire involves carefully cleaning and degreasing the wire surface, treating the surface with a reducing gas at an elevated temperature, and passing the wire continuously through a bath of molten aluminum metal. One difficulty is that the bath surface tends to oxidize, and the oxidation products tend to drag out on the surface of the freshly coated wire as it emerges from the bath. Fre quently also the wire has poorly coated areas known as black spots. These imperfections are of course objectionable in the finished product, and one known means for preventing them involves passing the freshly coated wire or other product through a partially confined body of reducing gas immediately as it emerges from the bath. The reducing gas prevents oxidation of the bath surface, and consequently there are no oxides present to drag out on the product. The problem' is less acute with other coating metals, such as zinc or tin, but the same principles apply.

An object of the present invention is to provide an improved device for partially confining a gas at the surface of a molten coating bath for wire, which device facilitates stringing the wire and subsequent maintenance.

A further object is to provide an improved device for preventing surface oxidation of molten metal coating baths in which each wire of a plurality passing through the bath has its own individual sleeve for partially confining a reducing gas in the region of its emergence from the bath.

A further object is to provide a device of the foregoing type in which wires can be strung through their respective sleeves without cutting and splicing them nor disturbing other wires passing through the same bath.

In accomplishing these and other objects of the invention, I have provided improved details of structure, preferred forms of which are shown in the accompanying drawings, in which:

Figure 1 is a top plan view of a protecting device constructed in accordance with my invention installed on a molten metal coating apparatus, the latter being shown only diagrammatically;

Figure 2 is a vertical section on a larger scale on line IIII of Figure 1; and

Figure 3 is a fragmentary top plan view, partly in section, showing a modification.

Figures 1 and 2 show diagrammatically a molten metal coating apparatus which comprises a vessel 10, a rigging 12 suspended from the top of said vessel, and a sink roll 13 journaled in said rigging. The vessel contains a bath 14 of molten metal such as aluminum approximately to the level indicated in Figure 2. A plurality of cleaned uncoated continuous wires W (five being shown) enter the bath from a supply at the left, pass under the sink roll, and emerge freshly coated at the right. A suitable take up mechanism for the .wires is located beyond the exit end of the apparatus. 'The drawing shows the wires traveling vertically beyondthe exit side of the sink roll, although they may slope from the vertical if desired. The bath is heated to the proper temperature and the temperature controlled by any suitable means not shown.

Inasmuch as the apparatus per se and its operation, apart from my novel protecting device, are well known, no more'detailed showing is deemed necessary.

In accordance with my invention, a transverse beam 15 extends across the top of the vessel 10 on the exit side of the rigging 12. This beam carries a bracket 16 which projects over the bath 14 above the level thereof and contains a plurality of circular openings 17, one for each wire W. The outer edge of the bracket contains access slots 18 for the respective openings 17. Each opening 17 receives an outer sleeve 19, and each outer sleeve an inner sleeve 20. The upper edge of each outer sleeve carries an integral supporting flange 21 which rests on the bracket 16 and has a truncated inner portion. The bracket has an upstanding rib 22 which the truncated portions abut to prevent rotation of the outer sleeves. The upper edge of each inner sleeve 20 carries an integral supporting flange 23 which rests on the respective flange 21 but allows free rotation of the inner sleeves. Preferably the sleeves are of refractory, such as silicon carbide, and their lower ends are immersed in the bath 14.

Each outer sleeve 19 has a longitudinal access slot '24 which extends the, full length of the sleeve contiguous to the respective access slot 18 in the bracket 16. Each outer sleeve also has a gas inlet port 25 located diametrically opposite its slot 24 above the level of the bath 14. Each inner sleeve 20 has a longitudinal access slot 26 which extendsthe full length of; the sleeve normally contiguous to the respective port 25 in the outer sleeve. However, the inner sleeve can be turned to align its slot 26 with the slots 18 and 24 in the bracket 16 and outer sleeve 19 to permit a wire W to be strung through the bore of the inner sleeve without cutting the wire. Behind the port 25 the bracket 16 carries a fitting 27 to which a flexible tube 28 is connected. Said tube extends to a gas line 29 which has a control valve 30.

In the modification shown in Figure 3 the bracket contains keyways 31 extending from its openings 17a. The exterior of each outer sleeve 1% has an integral key 32 which fits within the respective keyway to prevent rotation of the outer sleeves. Another equivalent arrangement would be to form the openings in the bracket and the exterior of the sleeve as non-circular in outline. The flange 21a at the top of the sleeve can be continuous except at the access slot.

In operation, each wire W is strung through its respective inner sleeve 20 in the manner already described. The wire lies approximately on the longitudinal center line of the sleeve. In an apparatus in which the wires slope from the vertical, the sleeves are supported at an appropriate angle to produce this relation. The wires are led continuously through the molten bath 14 and thus are coated with the metal thereof. A reducing gas is introduced to the inner sleeve 20, where it is partially confined, via the gas line 29, valve 30, tube 28, fitting 27, port 25 and slot 26. Examples of suitable gases are dissociated ammonia, natural gas or partially combusted natural gas. The gas prevents surface oxidation of the bath in the region where the wires emerge, and thus protects the freshly applied coating and produces a better coating on the finished product. Ordinarily the gas is ignited as it issues from the tops of the sleeves so as not to create any sort of hazard. The use of an individual sleeve for through its sleeve without disturbing the others, but also minimizes the volume of gas required. If a wire breaks, it can be restrung while the other wires continue to pass normally through the apparatus.

While I have shown and described certain preferred embodiments of my invention, it is apparent that other modifications may arise. Therefore, I do not wish to be limited to the disclosure set forth but only by the scope of the appended claims.

I claim:

l. The combination, with an apparatus for applying metal coating to wire, said apparatus including a vessel adapted to contain a bath of molten coating metal and a sink roll suspended in said vessel and under which the wire is adapted to pass, of a device for protecting the freshly applied coating as the wire emerges from the bath, said device comprising a supporting bracket mounted over said vessel, an outer sleeve fixed to said bracket lforconducting gas to the interior of said inner sleeve above the bath level.

2. The combination, with an apparatus for applying metal coating to a plurality of wires, said apparatus including a vessel adapted to contain a bath of molten coating metal and a sink roll suspended in said vessel and under which the wires are adapted to pass, of a device for protecting the freshly applied coating as the wires emerge from the bath, said device comprising a supporting bracket mounted over said vessel, a plurality of outer sleeves fixed to said bracket at the exit side of said sink roll, there being one sleeve for each wire, a plurality of inner sleeves, each of which is rotatably mounted in a different one of said outer sleeves, the upper ends of said sleeves being above the normal bath level and the lower ends being below, said sleeves having longitudinal slots extending their length through which the respective wires can be stnmg when any inner sleeve is turned to a position where its slot is aligned with that in the corresponding outer sleeve, and means for conducting gas to the interior of said inner sleeve above the bath level.

3. A protective device for wires emerging from a coating bath comprising a bracket, an outer refractory sleeve fixed in said bracket, an inner refractory sleeve rotatably mounted in said outer sleeve, said sleeves having longitudinal slots extendingtheir length through which a wire can be strung when the inner sleeve is turned to a position where its slotisaligned with-that in the outer sleeve, said slots being .ofiset arcuately when said inner sleeve is turned away from this position enabling the sleeves completely to enclose the wire, and means for conducting gas to the interior of said inner sleeve.

4. A protective device for wires emerging from a coating bath comprising a bracket having an opening and an access slot to said opening, an outer refractory sleeve non-rotatablyreceived in said opening and having a flange resting on the face of said bracketand a longitudinal slot extending its length contiguous to said access slot, an inner refractory sleeve rotatably received in said outer sleeve and having a flange .resting on the flange of said outer sleeve and a longtiudinalslot extending its length, said slots permitting a wire to be strung through said sleeves when the, inner sleeve is turned toa position where its slot is aligned with that in the outer sleeve, and means .for conducting gas to the interior of said inner sleeve.

5. A device as defined in claim 4 in which said last named means includes aport in said outer sleeve diametrically opposed to the longitudinal ,slot therein, a fitting carried by said bracket communicating with said port, and tubing connected to said fitting.

References-Cited in thefile of this patent UNITED STATES PATENTS 1,930,601 Townsend Oct. 17, 1933 1,994,802 Adams Mar. 19, 1935 2,010,941 Bradley Aug. 13, 1935 2,012,176 Tevander Aug. 20,1935 2,332,978 Ahern Oct. 26, 1943 

